We divide 437603 by 21
Let's see how many times 21 fits into 437603.

Step 1:
21 can be fit into 4 0 times, resulting in a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Include the next digit (3) from the dividend after 4, then repeat: 43 / 21

Moving on to step 2:
21 can be fit into 43 2 times, resulting in a remainder of 1.
Put 2 as the next digit of the answer. 
Result so far: 2.0
If we subtract 42 from 43, we get 1.
Take the next digit (7) from the dividend and append it to 1, then repeat: 17 / 21

Step 3:
21 can be fit into 17 0 times, resulting in a remainder of 17.
The number 0 becomes the next digit in our result. 
Result so far: 20.0
Subtract 0 from 17 to get 17.
Append the next digit (6) from the dividend to 17 and continue with: 176 / 21

Moving on to step 4:
21 goes into 176 8 times with a remainder of 8.
Put 8 as the next digit of the answer. 
Result so far: 208.0
Subtract 168 from 176 to get 8.
Bring next digit (0) of the dividend behind the 8 and repeat the process: 80 / 21

Moving on to step 5:
If we divide 80 by 21, we get 3 and a remainder of 17.
The next digit of our result is 3. 
Result so far: 2083.0
If we subtract 63 from 80, we get 17.
Bring next digit (3) of the dividend behind the 17 and repeat the process: 173 / 21

Step 6:
The number 21 fits into 173 8 times, leaving a remainder of 5.
Write down 8 as next digit of the result. 
Result so far: 20838.0
Subtracting 168 from 173 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Moving on to step 7:
If we divide 50 by 21, we get 2 and a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 20838.2
Deduct 42 from 50 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 8:
21 goes into 80 3 times with a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 20838.23
If we subtract 63 from 80, we get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

On to step 9:
When dividing 170 by 21, we get 8 with a remainder of 2.
Record the quotient 8 as the next digit in the result. 
Result so far: 20838.238
Subtracting 168 from 170 leaves us with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 10:
When dividing 20 by 21, we get 0 with a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 20838.238
The remainder is 20 after subtracting 0 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 11:
200 divided by 21 is 9 with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 20838.23809
If we take 189 away from 200, we end up with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Step 12:
110 divided by 21 is 5 with a remainder of 5.
The next digit of our result is 5. 
Result so far: 20838.238095
If we subtract 105 from 110, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 13:
50 divided by 21 is 2 with a remainder of 8.
The number 2 becomes the next digit in our result. 
Result so far: 20838.2380952
Subtract 42 from 50 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 14:
The number 21 fits into 80 3 times, leaving a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 20838.23809523
Subtracting 63 from 80 leaves us with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

After the division, we end up with 20838.23809523 and a remainder of 1.7e-08.